1. Field of the Invention
This invention relates generally to the local distribution of high bandwidth information signals.
2. Description of Related Art
There is a recognized demand to provide an inexpensive and efficient way to broadcast multimedia content within a specified small area using wireless solutions. Such small areas include single-family residential, multi-dwelling units, small/home offices, small businesses, multi-tenant buildings, and public and private campuses, all characterized by a restricted space, with numerous obstacles such as walls, furniture, metallic appliances, etc. There is a trend to provide the subscribers in this market with architectures that are comfortable, easy to use and attractively priced for consumers.
Current hardwire solutions require cabling hardware, with concomitant logistical overhead and aesthetic issues. Wireless methods are known, but such methods typically require significant compression prior to local distribution, and an a-priori reservation of wide, interference-free bandwidth. In addition, to make a wireless solution attractive from cost considerations point of view, the currently known architectures use, or propose to use, the un-licensed spectrum. Still further, wireless distribution of this type of signals in this type of environment is not a trivial task due to, for example, the interference between the signals in adjacent location, interference with other services present in the area, and the geography of the respective area.
For example, current local area distribution of high bandwidth information signals such as High-Definition Television (HDTV) signals has to conform to a variety of system constraints. As one illustrative example, a typical HDTV home system has a set top box (STB) connected to a service provider through an optical fiber, DSL link or satellite-downlink. The STB receives and decodes a Moving Picture Experts Group (MPEG) signal into a signal format compatible with the user's display. One common signal format uses the High-Definition Multimedia Interface (HDMI) technology. The HDMI formatted signal must then be transmitted to the user's video display. A hardwired connection is the most popular option for this connection. Frequently though, locations are without, or are not suitable for, high bandwidth hardwired systems. Further, aesthetic matters pertaining to cables may render such connections undesirable.
One potential wireless method is wireless HDTV. In such architecture, the set-top box decodes the MPEG data and then transmits it wirelessly over a 60 GHz band to the TV set via a built-in HDMI interface. While this solution reduces the cabling necessary for connecting the devices, it has important disadvantages. For example, a very high data link is needed since the data between the set-top and the TV set is not compressed. As well, the area in which the desired signal may be received with acceptable quality is quite small (up to a radius of 10 m). Some solutions proposed to address this issue involve the use of beam-forming technology, but this increases the costs and reduces the space available for the overall system hardware.
Another known solution for distributing a received information signal within an area, such as a residence or business establishment, is the conventional repeater. A conventional repeater receives the information signal, amplifies and retransmits it. However, conventional repeaters have shortcomings. One is that governmental and other imposed allocation of spectra may limit such conventional retransmission. Another is that a conventional repeater typically amplifies and repeats not only the information signal of interest but also various noise and interference signals. The result may be a degraded signal received by the end user.
Still another solution is use of Wi-Fi technology for in-house transmission, which operates in the 2.4 and 5 GHz unlicensed bands. However, conventional Wi-Fi may not provide a sufficient continuous data rate to satisfactorily support the HDTV picture quality. Further, link quality in Wi-Fi is often compromised due to various and often uncontrollable interference.